The European Union (EU) has established categories of allowable emissions in non-road diesel engines called Stages I, II, IIIA, IIIB and IV. Each increasing stage specifies lesser amounts of the four following specific pollutants that are permitted based on the number of grams per kilowatt-hour of the compounds present in diesel exhaust.
Nitrogen oxides (NOx)
NOx is a combustion by?product that combines in the atmosphere to create ozone and smog. It is controlled by reducing the combustion temperature inside the cylinder.
Essentially unburned fuel, HC contributes to ozone and smog production. HC is a minor constituent in diesel exhaust. Control is possible by improving combustion efficiency.
Carbon monoxide (CO)
CO is also a minor constituent of diesel exhaust. It is controlled by improving combustion efficiency.
Particulates are made up of soot particles in diesel exhaust from unburned carbon. Particulate matter is controlled by optimising the combustion temperature and improving combustion efficiency.
At present all EU portable, non-road gensets are required to meet Stage IIIA requirements (see table). A portable, non-road genset is considered to be either a rental set or a unit that is moved more than twice a year from a defined location. The Stage IIIA regulations only affect portable and rental generator sets in the power range of 18?560 kVA.
The EU does not, however, regulate emissions from stationary, non-road diesel generator sets such as those used for prime, peak shaving, load shedding or emergency standby power. Whether this situation will remain the case for much longer is very much open for debate.
Critical Power asked members of the Association of Manufacturers of Power Generation Systems’ (AMPS) technical committee if, how and when the European Commission will move to impose regulations on stationary generator sets in prime and/or critical power applications.
Roger Lane-Nott, Director-General, AMPS
It is not a question of if it is going to happen. It is a question of when it is going to happen. I attend many meetings in Brussels and I get a good feel for the trends for the industry.
It’s difficult to say when the Commission will regulate, but it could be as soon as 1-2 years. It certainly will not be any sooner than that because there is too much paperwork involved with the process, but I am convinced it will happen.
We talk to the Commission on a regular basis. Sometimes they give you advance warning and sometimes they keep it to themselves until absolutely sure they can deliver it. We are constantly talking to them and trying to squeeze information out of them. The problem is there is no ‘intelligence unit’ in Brussels, but I go to all the meetings and talk to them both formally and informally.
The Commission has clear ideas about what they like to do but what is in their heads is often miles ahead of what they actually can achieve, as it has so much going on. Inevitably, complex legislation takes time and there is no way of shortening the process.
Whether diesel engine and genset OEMs are able to meet any stricter regulation is very much dependent on what the Commission comes up with and how vicious it will be. One of our problems at AMPS is that the Commission is very much on the side of the consumer and they do not really care about anyone else.
Some manufacturers will be unhappy, but whether they’ll fight it is another matter. It all depends on what the Commission moves to regulate. With it be carbon dioxide, nitrous oxide or other emissions?
The European Commission hasn’t issued a communiqué on this, but it will be on their long list of things to do. You can never really tell with the Commission, they set dates, but they don’t always stick to them, it depends on what input and get feedback they get from the industry. You can never really guarantee anything going on in Brussels, all you can do is follow the trends and see where things are headed. But, before you know it, things will start to happen.
Richard Payne, Off-Highway Regulatory Affairs Director for Europe, Cummins Ltd.
I do not think it is possible for the Commission to regulate stationary engines within a year or two, it will take them at least five years. It takes them 5-10 years to do anything from scratch. So we are looking at 2017 onwards, I do not think EU wide regulation for stationary engines could possibly arrive before that.
As a company, Cummins wants the Commission to introduce standards consistently across Europe, as has happened in the United States. We as an industry are trying to encourage the Commission to regulate stationary engines below, as well as above, 560 kVA. I am personally working with the small engine industry to regulate stationary engines, which are based on mobile equipment engines, in the same way as mobile equipment.
From 2014 onwards variable speed mobile engines are subject to stringent stage IV limits. The proposal would be to introduce these to mobile constant speed engines and stationary engines at the same time.
We are talking to the Commission about adopting similar regulation for stationary engines of up to 5 MW thermal, equivalent to about a 2.2 MVA genset, then adopting the United Nations Economic Commission for Europe (UNECE) Gothenburg Protocol, for gensets sized between 5-50 MWthermal. Gensets above 50 MW thermal are covered by the Industrial Emissions Directive, although there is talk about bringing that down to 20 MW.
Emissions regulation would primarily cover NOx, CO, unburned hydrocarbons and particulate matter, it is unlikely that the Commission would regulate CO2 emissions at this point in time; they are working on the on-road vehicles first. Having regulations should not impose a problem, but at the moment different countries have different regulations - we want the same right across Europe. While several countries have their own regulations for prime power generating sets, Germany’s TA Luft perhaps being the most widely known, we want EU-wide regulation.
Regulation for stationary engines is probably harder to justify than for mobile engines due to their portability, but a level playing field across the EU would not allow different areas of Europe to apply different standards depending on their needs. However the cost benefits of regulating stationary engines are great, enabling us to standardise production of our technology and achieve the greatest benefit to air quality across the EU at lowest cost.
Richard Cotterell, General Manager of Perkins’ Large Engine Centre, UK
We are engaged via various industry bodies with the EU. The EU is quite logical and very good about consulting over emissions control of diesel engines but you cannot always predict what it is going to do.
In general, we are very happy with the way the EU manages its relationship with engine and genset manufacturers. Other countries and regions can suddenly announce measures out of the blue with little means of support for manufacturers. Singapore did this recently.
The EU may move to a US Tier?4 style regulation for diesel stationary engines, but that is difficult to predict. But whatever comes down the track from Brussels, history has shown that we have sufficient time to introduce the necessary technology to meet stricter admissions requirements. We have a range of engines that meet emissions regulations around the world.
France, Germany and Switzerland and other European countries have their own regulations. India, for example, regulates diesel engines up to 800 kVA, whereas the EU only regulates [non-road, portable gensets] up to 560 kW.
Furthermore, the emissions regulations set for electric power engines are several years behind highway engines, so as Perkins also manufactures on-highway engines we are less apprehensive about more stringent emissions legislation. Our electric power division in Stafford, UK will be able to leverage Perkins in-house expertise and knowledge that our brothers have in Peterborough, as well as our parent company Caterpillar has around the world.
Robert Ralphs, Technical Director, IPU Group
Regulation is coming over the horizon and the industry needs to be ready for it. In their infinite wisdom, engine manufacturers do not want to make different products for different markets, so the chances are the regulation for non-road, stationary engines is going to be almost as strict as for non-road, portable engines.
Standardisation is very important to them so, whatever comes over the horizon, I suspect engine manufacturers will want to be able to meet any new regulation with existing technology, or technology currently being developed to meet regulations for on-highway, portable applications. Off-highway application engine regulations follow on-highway several years later.
While low CO2 emissions are a sign of high fuel efficiency of a diesel engine, there’s very little chance the European Commission would regulate this. They are going to regulate oxides of nitrogen, particulates and hydrocarbons.
Non-road, stationary engines are probably the toughest for the European Commission to regulate because on-highway engines already have sufficient infrastructure in place for ultra low sulphur diesel and for AdBlue (a diesel exhaust fluid used in selective catalytic reduction to lower NOx concentration).
Getting hold of AdBlue for non-road, stationary engines is potentially difficult. If somebody hires a 1 MW genset, for example, and new regulations require AdBlue to be added, then the company will need an additional bunded tank by the side of the unit.
For IPU, we would have to adapt our engine controls to any new regulations. But this is more software than hardware. With engines above 560 kVA, all control systems will be electronic so we just have to make sure that we can interface with the latest cam systems.
Fuel conditioning will be critical to meeting any stricter emissions for stationary engines. You need after-treatments. Particulate traps don’t like sulphur because when you burn sulphur in a diesel engine it creates sulphates, which block up filters. Also, with modern, high-pressure common rail diesel injection systems you are talking machining tolerances of three microns inside injectors. Unless you have exceedingly clean fuel low in sulphur you have all sorts of issues with injector lifetime and injector performance, which must be a critical part of any emissions strategy.
For more information and advice about gensets visit www.amps.org.uk